#!/usr/bin/env bash

#  helper script: download coreboot
#
#	Copyright (C) 2014, 2015, 2016, 2020, 2021 Leah Rowe <info@minifree.org>
#
#	This program is free software: you can redistribute it and/or modify
#	it under the terms of the GNU General Public License as published by
#	the Free Software Foundation, either version 3 of the License, or
#	(at your option) any later version.
#
#	This program is distributed in the hope that it will be useful,
#	but WITHOUT ANY WARRANTY; without even the implied warranty of
#	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#	GNU General Public License for more details.
#
#	You should have received a copy of the GNU General Public License
#	along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

[ "x${DEBUG+set}" = 'xset' ] && set -v
set -u -e

# Error handling is extreme in this script.
# This script handles the internet, and Git. Both are inherently unreliable.

[[ -f build_error ]] && rm -f build_error

rm -f resources/coreboot/*/seen

downloadfor() {

	board="${1}"
	cbtree="undefined"
	cbrevision="undefined"

	# The loop will always exit, but this while loop is crafted
	# such that a tree referencing a tree that references another tree is possible
	# (and so on)
	while true; do
		cbrevision="undefined"
		cbtree="undefined"

		if [ ! -f "resources/coreboot/${board}/board.cfg" ]; then
			printf "ERROR: download/coreboot: board.cfg does not exist for '%s'\n" "${board}"
			return 1
		fi

		if [ -f "resources/coreboot/${board}/seen" ]; then
			printf "ERROR: download/coreboot: logical loop; '%s' board.cfg refers to another tree, which ultimately refers back to '%s'.\n" "${board}" "${board}"
			return 1
		fi

		# This is to override $cbrevision and $cbtree
		source "resources/coreboot/${board}/board.cfg" || touch ../build_error
		if [ -f build_error ]; then
			printf "ERROR: download/coreboot: problem sourcing %s/board.cfg\n" "${board}"
			return 1
		fi
		touch "resources/coreboot/${board}/seen"

		if [ "${board}" != "${cbtree}" ]; then
			board="${cbtree}"
		else
			if [ "${cbtree}" = "undefined" ]; then
				printf "ERROR: download/coreboot: tree name undefined for '%s\n'" "${board}"
				return 1
			fi

			if [ "${cbrevision}" = "undefined" ]; then
				printf "ERROR: download/coreboot: commit ID undefined for '%s'\n" "${board}"
				return 1
			fi
			break
		fi
	done

	rm -f resources/coreboot/*/seen

	if [ -d "coreboot/${cbtree}" ]; then
		printf "REMARK: download/coreboot: directory for '%s' already exists. Skipping setup.\n" "${cbtree}"
		if [ "${cbtree}" != "${1}" ]; then
			printf "(for board: '${1}')\n"
		fi
		return 0
	fi

	if [ ! -d coreboot ]; then
		mkdir "coreboot/"
	fi
	if [ ! -d coreboot ]; then
		printf "ERROR: download/coreboot: directory not created. Check file system permissions\n"
		return 1
	fi

	cd "coreboot/"

	if [ ! -d coreboot/.git ] && [ -d coreboot ]; then
		rm -Rf coreboot/
	fi

	if [ ! -d coreboot ]; then
		printf "Download coreboot from upstream:\n"
		git clone https://review.coreboot.org/coreboot || rm -Rf coreboot
		if [ ! -d coreboot ]; then
			printf "WARNING: Upstream failed. Trying backup github repository:\n"
			git clone https://github.com/coreboot/coreboot.git || rm -Rf coreboot
		fi
		if [ ! -d coreboot ]; then 
			printf "ERROR: download/coreboot: Problem with git-clone. Network issue?\n"
			cd ../; return 1
		fi
	else
		( cd coreboot/; git pull || touch ../build_error )
		if [ -f ../build_error ]; then
			printf "ERROR: download/coreboot: Problem with git-pull. Network issue?\n"
			cd ../; return 1
		fi
	fi

	cp -R coreboot "${cbtree}" || touch ../build_error
	if [ -d ../build_error ]; then
		printf "ERROR: download/coreboot: Unable to copy directory. Check file system permissions or free space.\n"
		rm -Rf "${cbtree}/"
		cd ../; return 1
	fi

	cd ${cbtree}/

	git reset --hard ${cbrevision} || touch ../../build_error
	if [ -f ../../build_error ]; then
		printf "ERROR: download/coreboot: Unable to reset to commit ID/tag '%s' for board '%s' on tree '%s'\n" "${cbrevision}" "${1}" "${cbtree}"
		cd ../../; return 1
	fi

	git submodule update --init --checkout || touch ../../build_error
	if [ -f ../../build_error ]; then
		printf "ERROR: download/coreboot: Unable to update submodules for tree '%s'\n" "${cbtree}"
		cd ../../; return 1
	fi

	for patch in ../../resources/coreboot/${cbtree}/patches/*.patch; do
		if [ ! -f "${patch}" ]; then
			continue
		fi

		git am "${patch}" || touch ../../build_error
		if [ -f ../../build_error ]; then
			printf "ERROR: download/coreboot: Unable to apply patch '%s' for board '%s' on tree '%s'" "${patch}" "${1}" "${cbtree}"
			git am --abort
			cd ../../; return 1
		fi
	done

	# extra.sh could be used to patch submodules, if you wanted to
	# It's impossible to predict what submodules will be available, and
	# it's rare that you'd want to patch them, so this is handled by
	# extra.sh on a per-board basis
	# In fact, extra.sh can be used for anything you want.
	if [ -f "../../resources/coreboot/${board}/extra.sh" ]; then
		"../../resources/coreboot/${board}/extra.sh" || touch ../../build_error
		if [ -f ../../build_error ]; then
			cd ../../; return 1
		fi
		return 0
	else
		cd ../../
		return 0
	fi
}

printf "Downloading coreboot and (if exist in build system) applying patches\n"

if [ $# -gt 0 ]; then
	for board in "${@}"; do
		rm -f resources/coreboot/*/seen
		downloadfor "${board}"
		if [ -f build_error ]; then break; fi
	done
else
	for board in resources/coreboot/*; do
		rm -f resources/coreboot/*/seen
		if [ ! -d "${board}/" ]; then
			continue
		fi
		downloadfor "${board##*/}"
		if [ -f build_error ]; then break; fi
	done
fi

rm -f resources/coreboot/*/seen

rm -f "build_error"
printf "\n\n"
exit 0
